1. Field of the Invention
The present invention relates to a structure for mounting a solid-state image pick-up device such as a CCD on a supporting member, e.g., a housing of a lens barrel of a digital camera.
2. Description of the Related Art
When a CCD (charge coupled device) serving as a solid-state image pick-up device is mounted on a housing, e.g., a housing of a lens barrel of a digital camera, an inclination of an image captured by the CCD occurs if the CCD is not mounted on the housing at a proper mounting angle.
Accordingly, the CCD needs to be fixed to the housing after the mounting angle of the CCD is set at an optimum angle by visual inspection of a chart image formed on the CCD or by computer processing of an image formed on the CCD.
According to a known mounting structure, firstly a CCD is temporarily fixed by set screws to a fixing plate fixed to a housing, a spacer is then inserted in between the fixing plate and the CCD to set the mounting angle of the CCD at optimum angle, and finally the CCD is permanently fixed to the fixing plate by fastening the set screws. According to another known mounting structure, a set of three compression helical springs are held between a CCD and a fixing plate to which the CCD is fixed while a set of three set screws which are inserted through the fixing plate and the set of three compression helical springs are screwed into a set of three screw holes formed on a housing, respectively, so that the mounting angle of the CCD with respect to the housing can be adjusted by adjusting the amount of engagement of each set screw with each corresponding screw hole.
However, according to the former mounting structure which uses a spacer, when the mounting angle of the CCD is adjusted, the spacer needs to be replaced by another spacer having a different thickness after the set screws are temporarily removed, and thereafter the set screws need to be fastened again. This is troublesome and time-consuming.
On the other hand, according to the latter mounting structure using a set of compression helical springs, a gap exits between the fixing plate and the housing. Due to this structure, the fixing plate tilts if pushed toward the housing, which makes it impossible to maintain an optimum mounting angle for the CCD.
The present invention provides a mounting structure of a solid-state image pick-up device which makes it easy to adjust the mounting angle of the image pick-up device with respect to a supporting member of the image pickup device to an optimum angle, and which makes it possible to maintain the mounting angle at optimum angle even if an external force is applied to a fixing plate to which the CCD is fixed.
For example, a mounting structure for mounting an image pick-up device on a supporting member in such a manner that a mounting angle of the image pick-up device is adjustable with respect to the supporting member, the mounting structure including a fixing plate to which the image pick-up device is fixed; a plurality of screw holes formed on the supporting member on the fixing plate side; a first female threaded portion and a second female threaded portion, having a diameter smaller than a diameter of the first female threaded portion, which are formed in each the plurality of screw holes in that order from the fixing plate side; a plurality of cylindrical adjustment members which are screwed into the plurality of screw holes, respectively, each the plurality of cylindrical adjustment members having a male threaded portion, which is engaged with corresponding the first female threaded portion and an axial hole, the cylindrical members being rotatable to adjust the axial position thereof; and a plurality of set screws which are rotatably inserted through the fixing plate and the respective axial holes of the plurality of cylindrical adjustment members to be engaged with the second female threaded portions of the plurality of screw holes to hold the fixing plate between each head portion of the plurality of set screws and each the plurality of cylindrical adjustment members, respectively.
It is desirable for each of the plurality of cylindrical adjustment members to include a supporting surface for holding the fixing plate between the supporting members of the plurality of cylindrical adjustment members and the plurality of set screws.
The plurality of screw holes can be formed on the supporting member at different radial positions about a center of the image pick-up device.
It is desirable for each of the plurality of cylindrical adjustment members to include an adjustment gear portion provided outside corresponding one of the plurality of screw holes.
The supporting member can include at least one positioning hole in which a tip of a jig having a gear engageable with the adjustment gear portion can be engaged so that the tip is freely rotatable in the positioning hole.
The mounting structure can further include a plurality of spring members held between the head portions of the plurality of set screws and the fixing member to bias the head portions and the fixing member in opposite directions away from each other, respectively.
The supporting member can serve as a housing of a lens barrel of a digital camera.
It is desirable for there to be at least three screw holes, at least three cylindrical adjustment members, and at least three set screws.
It is desirable for each of the plurality of spring members to be a spring washer.
The supporting member can include a plurality of positioning holes in the vicinity of the plurality of cylindrical adjustment members, respectively, wherein a tip of a jig having a gear which is engageable with the adjustment gear portion can be engaged in any one of the plurality of positioning holes so that the tip is freely rotatable therein.
According to another embodiment, a mounting structure is provided for mounting an image pick-up device on a supporting member in such a manner that a mounting angle of the image pick-up device is adjustable with respect to the supporting member, the mounting structure including a fixing plate to which the image pick-up device is fixed; three screw holes formed on the supporting member to extend in a direction substantially orthogonal to a sensitive surface of the image pick-up device, a large-diameter female threaded portion and a small-diameter female threaded portion being formed in each of the three screw holes in that order from the fixing plate side; three cylindrical adjustment members which are screwed into the three screw holes, respectively, each the three cylindrical adjustment members having a male threaded portion which is engaged with corresponding the large-diameter female threaded portion so that a position of each of the three cylindrical adjustment members can be adjusted with respect to the supporting member by rotating the each of the three cylindrical adjustment members; and three set screws which are inserted through the fixing plate 29 and respective axial holes of the three cylindrical adjustment members to be engaged with the small-diameter female threaded portions of the three screw holes to hold the fixing plate between head portions of the three set screws and the three cylindrical adjustment members, respectively.
The mounting structure can further include a rotational-adjustment device for rotating each the three cylindrical adjustment members to adjust the position of each the three cylindrical adjustment members with respect to the supporting member.
The present disclosure relates to subject matter contained in Japanese Patent Application No.2001-259449 (filed on Aug. 29, 2001) which is expressly incorporated herein by reference in its entirety.